Passenger vehicles often include electric batteries for operating features of a vehicle's electrical and drivetrain systems. For example, vehicles commonly include a 12V lead-acid automotive battery configured to supply electric energy to vehicle starter systems (e.g., a starter motor), lighting systems, and/or ignition systems. In electric, fuel cell (“FC”), and/or hybrid vehicles, a high voltage (“HV”) battery system (e.g., a 360V HV battery system) may be used to power electric drivetrain components of the vehicle (e.g., electric drive motors and the like). For example, an HV rechargeable energy storage system (“ESS”) included in a vehicle may be used to power electric drivetrain components of the vehicle.
Information regarding power capability of a battery system may be utilized in modeling battery system performance and/or in connection with battery system control and/or management decisions. A battery state estimation (“BSE”) system may be used to predict power capability of a battery system. Under most operating conditions, a battery system may have a power capability that exceeds the capabilities of associated motors and power electronics in a vehicle. For low temperature operation, however, electrochemical processes at work within the battery system may be slowed to point that there remains little margin to meet the power demands of the system. An accurate estimate of battery system power capability may be important in such a situation. A small over-prediction of power capability can lead to failed attempts to crank an engine or erratic vehicle acceleration, while a similarly small under-prediction of power can temporarily disable the propulsion system. Therefore, a BSE system that properly interprets the effects of low temperature on the battery is desirable.